Audi offers two flavors of its R8 supercar, the 4.2-liter V-8 version with 420 hp, and the 5.2-liter V-10 version with 525 hp. If you need more power, Heffner Performance has cranked the V-8 version up to a claimed 625 hp.

Heffner supplements the V-8 with twin Garrett GT28 turbochargers for a combined 6 psi of boost. Using 91- or 93-octane gasoline, 625 hp is available. Running on 100-octane fuel reportedly helps generate up to 685 ponies.

Tweaks include custom intercoolers, exhausts, and a remapped engine computer. Heffner tells us the stock clutch holds up despite the 205-hp power increase. And because the factory catalytic converters are retained, the R8 should still be emissions legal in all states but California.

Heffner can attach the turbos to any V-8–powered R8 for about $32,000. The first kits should be ready by the end of this month. The Florida-based tuner has impressed us in the past with boosted Lamborghinis and Ford GTs and this package will likely do the same.